Microsoft has quietly increased the prices of its Office for Mac 2011 by as much as 17 percent, putting it on price par with Office 2013 for Windows.

The software giant has also quit selling multi-license packages, which allowed customers to purchase multiple copies of the application suite at a discounted rate.

The single-license Office for Mac Home & Student now costs $140, an increase of about 17 percent from the previous price of $120. Meanwhile, Microsoft raised the price of Office for Mac Home & Business, which includes Outlook, to $220, a 10 percent increase over the previous $200 price.

Microsoft doesn't seem to have publicized the price increase, so it's not clear when the price increase took effect. However, Computerworld, which first reported the increase, estimates it occurred around January 29, the same day that Microsoft Office 2013 and Office 365 were launched.

CNET has contacted Microsoft for more information on the price increase and will update this report when we learn more.

In addition to the price increase, Microsoft ceased sales of multi-license editions. The multi-user packs are still for sale on Amazon (while supplies last) at a significant discount, but the listing notes that the software is an older edition.

The moves are apparently intended to redirect customers toward Office 365, which costs $100 for an annual subscription. The new offering is part of effort by Microsoft to bring its suite of Office server tools and collaboration work flows into the cloud.